Designing a connecting rod, I'd love some insights on how stock rods fail etc.

[bob58o]

It's not that complicated to do, my 208 is running a 12v external pump, remote filter, a check valve sandwich block, and an oil cooler.

If I wanted to make it a little more a true to trait pressurized system, I'd just relocate the return port to the topside where the governor linkage plug is

This side cover looks like the return somehow goes to the crank bearing in the cover. Not sure how it gets dispersed from there.

 

[Rat]

This side cover looks like the return somehow goes to the crank bearing in the cover. Not sure how it gets dispersed from there.

Most likely the outer shell has a groove and hole drilled through off center to not disrupt the race surface.

I remove the inner seals when I replace crank bearings. Having them skinny dip is just more effective than any forced lubrication mod one could cook up.
We've established repeatedly on this forum that the fastest way to spew and actually loose oil is having too much oil get up into the valvetrain.

Ideally the closest most efficient mod to do a pressurized oil system on any small displacement engine not originally designed with one is to drill and tap a fitting to pump oil directly through the top and pouring down in line with the conrod... the governor linkage port is surprisingly close to that.

 

[bob58o]

Most likely the outer shell has a groove and hole drilled through off center to not disrupt the race surface.

I remove the inner seals when I replace crank bearings. Having them skinny dip is just more effective than any forced lubrication mod one could cook up.
We've established repeatedly on this forum that the fastest way to spew and actually loose oil is having too much oil get up into the valvetrain.

Ideally the closest most efficient mod to do a pressurized oil system on any small displacement engine not originally designed with one is to drill and tap a fitting to pump oil directly through the top and pouring down in line with the conrod... the governor linkage port is surprisingly close to that.

Have you modded Honda /clones engines to enlarge to oil drain between the pushrods? I done that few times.

 

[busted_blocks]

I had a machining company shell my gx390 cast rod, never had any problem with it failing, just wearing out the shells.

I think you mentioned that in one of the early messages. That was part of the inspiration for trying to add the shells. It also give me pretty good hope that it will work.

 

[busted_blocks]

It’s been a while, since I watched this.
200cc utility engine with pressurized lube / oil pump.

View attachment 145945

That is a prety sweet engine. I saw he replaced the crank shaft. the one he took out had a hole for oil in the crank under the connecting rod. That does look like a good way to get oil to the connecting rod

 

[Rat]

Have you modded Honda /clones engines to enlarge to oil drain between the pushrods? I done that few times.

I have but it doesn't allow as much draining as it allows more oil to be plug up and besides that it really can't be enlarged by any real significant amount